This monster can only be Ritual Summoned with the Ritual Spell Card "White Dragon Ritual." You must also Tribute monsters whose total Levels equal 4 or more from the field or your hand. When this monster attacks a face-down Defense Position monster, destroy the face-down monster with this card's effect without flipping it face-up or damage calculation. You can Tribute this card to Special Summon 1 "Blue-Eyes White Dragon" from your hand or your Deck. ("Blue-Eyes White Dragon" cannot attack during that turn.)